The present invention relates to a thermally reflective substrate coating and a method for making and applying such a coating, and more particularly a wrap coating which may be applied to profiles such as those used to form architectural or automotive components and which has improved scratch and distortion resistance.
Various spray coatings have been proposed for use in reducing the temperature rise associated with sun light exposure on metallic and non-metallic substrates. One such coating is disclosed in U.S. Pat. No. 4,546,045 to Elias, which issued Oct. 8, 1985, and involves the application of a paint composition comprised of a film forming polymer and an infrared reflective pigment to polyvinyl chloride (PVC) substrate profile. Following the application of the coating composition, the substrate profile is baked at 130xc2x0 F. for approximately twenty minutes to ensure proper coating adhesion to the substrate profile.
A difficulty with conventional coating techniques exists in that depending upon the substrate or profile to be coated, it may not be economically or physically possible to bake the painted PVC profile to provide the required curing for proper adhesion of the thermally reflective paint. In particular, often it is desirable to provide coatings to PVC profiles which are used in the formation of architectural components such as pilasters, windows and doors. Such profiles are manufactured off site and are coated as elongated PVC or other plastic extrusions prior to final door or window assembly. Similarly, it is envisioned that various plastic profiles used in the automotive industry to form bumpers, fenders and other auto parts may be too large or cumbersome to heat cure and achieve the necessary adhesion of the thermally reflective paint.
Accordingly, it is an object of the present invention to overcome at least some of the disadvantages of the prior art by providing a thermally reflective wrap coating which may be applied as a coating to a number of different profiles made from wood, metal, or American Architectural Manufacturer""s Association (AAMA) #303 certified plastics including polyvinyl chloride (PVC), sheet molding compound (SMC), acrylonitrile-butadiene-styrene resins (ABS), polyphenylene oxide (PPO), nylon, polystyrene, fibreglass and any other non-metallic or synthetic substrates including those suitable for use as architectural and/or automotive components.
Another object of the invention is to provide a coloured wrap coating for substrate profiles which includes a thermally reflective paint or pigment layer, and which may be secured to an exposed surface of the profile by conventional processes, including cold and/or hot gluing, sonic welding, hot welding, and the like.
Another object of the invention is to provide a wrap coating for non-metallic materials made from AAMA plastics which provides material with increased thermal reflectivity and ultra-violet (UV) protection, to prolong the product life.
Another object of the invention is to provide architectural or automotive components with factory-applied organic coatings, which will provide and maintain a superior level of performance in terms of film integrity, exterior weatherability and general appearance over a period of many years.
The invention resides in an improved flexible film wrap which may be used to coat both metallic and non-metallic profiles, including wood and plastics, and which preferably include profiles used as architectural and/or automotive components. The film wrap includes a PVC backing layer or sheet which is bonded and at least partially cross-linked to a polyvinyl fluoride (PVF) film layer, and a paint or pigment layer applied to the PVF layer. Most preferably, the pigment layer is thermally reflective paint, as for example is disclosed in U.S. Pat. No. 4,546,045 to Elias.
To form the film wrap, a first surface of a flexible 0.5 to 3 mil thick sheet of PVF is aligned overtop of a flexible 1 to 7 mil thick sheet of PVC. Following the alignment of the PVC and PVF sheets, a third layer of the thermally reflective paint is then applied to the second other exposed surface of the PVF sheet and the three layers are heated. Most preferably, heating occurs at between approximately 275xc2x0 and 375xc2x0 F. for approximately 1 to 10 minutes until such time as the PVC and PVF sheets fuse to each other, resulting in at least partial cross-linking therebetween, and the paint or the pigment layer cures and fuses to the PVF sheet.
The paint layer may be: applied to the PVF sheet in a number of different manners, as for example, by spraying, brush coating or roll coating. Most preferably, the paint layer is applied as a layer having a wet thickness of about 0.5 to 3 mil, and dries to a thickness of 0.5 to 1.2 mil, and more preferably 0.8 to 1 mil.
It has been found that the wrap coating may be secured as a covering layer to a number of different profiles. Most advantageous, however, it has been found that the PVC backing of the wrap coating may be secured to an exposed surface of a non-metallic profile, including those made from PVC, SMC, ABS, PPO, nylon, polystyrene and fiberglass, which are used to form either architectural components such as pilasters, window and door frames, or automotive components such as bumpers, dash boards, consoles and the like. The wrap coating may be secured to the profiles in a number of conventional manners, including by cold gluing, heat welding or fusing and sonic welding. The applicant has appreciated, however, one preferred method whereby a polyurethane reactive hot-melt glue is used to secure the PVC backing layer of the coating directly to the profile.
Accordingly, in one aspect the present invention resides in a thermally reflective flexible wrap for use in coating articles, comprising
a polyvinyl chloride backing layer,
a polyvinyl fluoride layer at least partially crossed linked to the backing layer, and a pigment coating layer applied to the polyvinyl fluoride layer, said pigment coating layer having a thickness selected at between 0.5 and 2 mils.
In another aspect, the present invention resides in a method of manufacturing a flexible thermally reflective coating wrap comprising a polyvinyl chloride backing sheet, a polyvinyl fluoride sheet at least partially, crossed linked to the backing layer, and a pigment coating layer applied to the polyvinyl fluoride layer having a thickness selected at between 0.5 and 2 mils, said coating wrap being formed by the steps of,
positioning a first surface said polyvinyl fluoride sheet in overlying juxtaposition with a first surface said polyvinyl chloride sheet;
applying said pigment to a second other surface of said polyvinyl fluoride sheet; and heating said polyvinyl chloride sheet, said polyvinyl fluoride sheet and said pigment at a temperature selected at between about 250 and 400xc2x0 F. to substantially cure said pigment and at least partially cross link polyvinyl fluoride sheet and said polyvinyl chloride sheet to each other.
In a further aspect, the present invention resides in a process for coating a substrate with a thermally reflective film coating,
said film coating comprising a polyvinyl chloride backing layer, a polyvinyl fluoride layer at least partially crossed linked to the backing layer, and a pigment coating layer applied to the polyvinyl fluoride layer having a dry thickness selected at between 0.5 and 2 mils,
said substrate being coated by the steps of
applying a hot melt glue in a melted state to an exposed surface of said substrate; while said hot melt glue remains in said melted state positioning said film coating on said exposed surface.
In a further aspect, the present invention resides in a coated component comprising a non-metallic substrate selected from an architectural component and an automotive part component, and a thermally reflective wrap secured to at least one exposed surface of said non-metallic substrate, said wrap comprising
a polyvinyl chloride backing layer,
a polyvinyl fluoride layer at least partially crossed linked to the backing layer, and a pigment coating layer applied to the polyvinyl fluoride layer, said pigment coating layer having a thickness selected at between 0.5 and 2 mils.